Blending wood pitch with fatty acid pitch



Patented Nov. 7, 1933 BLENDING woon PITCH WITH FATTY ACID PITC Louis J.Figg, Jr., Kingsport, Tenn., assignor to Eastman Kodak Company,Rochester, N. Y., a corporation of New York No Drawing. ApplicationJanuary 15, 1932 Serial No. 586,972

2 Claims.

duce stables, viscous, homogeneous mixtures of Wood pitch with fattyacid pitch.

5 Generally speaking, wood pitch is not compatible with fatty acidpitch. When the two are mixed, the product separates into two distinctlayers. Various emulsifying agents have been tried in an attempt toproduce a satisfactory blended pitch, but without success. Solventscommon to both pitches have also been tried, but the resultant productis usually so thin as to be useless, and furthermore, as the solventevaporates, separation of the two component pitches takes place.

I have discovered that it is possible to produce stable, viscous,homogeneous mixtures of wood pitch with fatty acid pitch by heatingtogether pitches having approximately the same flow point. Pitches ofany desired flow point, from 35 C. to 120 C., may be used, provided thatthe wood pitch and the fatty acid pitch used have approximately the sameflow points. For example, wocd pitch having a flow point of 98 C.

may be heated in an open vessel or closed still with fatty acid pitchhaving a flow point of 95 C. until complete solution is produced. I havefound it possible in this manner to blend wood pitch with fatty acidpitch in any desired proportions. The wood pitch must be free fromlumps, coked tar, charcoal, wood fiber, etc.

If it is desired to obtain a product of higher flow point than that ofthe pitches mixed, the flow point may be raised by heating the mixtureto drive ofi volatile matter until the desired flow point is attained.The heating may be carried out under vacuum or at atmospheric pressure.If it is done in an open vessel, the vessel should expose as littlesurface of the mixture as possible. Agitation should be avoided duringthe blending and heating.

The following is an example of the method of carrying out my invention.Two parts by weight of stripped settled tar from hardwood distillation,having a flow point of 35 C., (measured by the ball and ring method),and one part by weight of fatty acid pitch having a flow point of 35 C.were heated together without agitation at a temperature of 150 C. untilthe flow point of the mixture reached 75 C. The mixture was then pouredinto a container and allowed to cool. Cross sections of the resultantproduct showed a complete mixing. Flow points taken at the top andbottom of the mix were found to be the same as the flow point of the mixas a whole.

It will be understood that the above example is merely illustrative, andthat my invention is not limited to the particular materials,prcportions, temperatures or flow points mentioned in the example. Theflow point of the starting materials may be any temperature from 35 C.to 120 C., and the flow point of the final product may be anytemperature from 35 C. to 120 0., except that the flow point of thefinal product will not, of course, be lower than that of the startingmaterials. The temperature at which the mixture is heated may be from150 C.

to 250 C. The proportions in which the pitches are mixed may be anydesired proportions. The wood pitch may be stripped settled hardwoodtar, copper still tar, pine tar, or any other wood tar obtained from thedestructive distillation of wood. The fatty acid pitch may be stearinpitch, black grease obtained in the manufacture of soap, the residualtar obtained in the distillation of cotton seed oil, or any other pitchobtained from fatty acids or animal or vegetable greases.

My novel compositions of wood pitch and fatty acid pitch may be used asa substitute for pure fatty acid pitch for blending with gilsonite. Thegilsonite may be added to the pitches either before or after the pitchesare blended.

What I claim as my invention and desire to be secured by Letters Patentof the United States is:

1. A process of producing a stable, viscous, homogeneous mixture of awood pitch with a fatty acid pitch, which comprises heating a wood pitchwith a fatty acid pitch of approximately the same flow point.

2. A process of producing a' stable, viscous, homogeneous mixture ofaWood pitch with a fatty acid pitch, said mixture having a flow pointhigher than that of the individual pitches, comprising heating a woodpitch with a fatty acid pitch of approximately the same flow point, andcontinuing the heating until the flow point of the product is raised.

LOUIS J. FIGG, JR.

